Research Of The Two Piezoelectric Stacks Driven Jetting Dispenser With A Flexure Beam

Adhesive dispensing is an important part in microelectronic packaging process and jetting dispensing technology with high consistency, high production efficiency and wide range of application presently becomes the fastest developing areas in all types of dispensing technology. In order to realize high frequency and excellent performance jetting dispensing, a new kind of jetting dispenser with flexible beam driven by two piezoelectric stacks was designed.In this paper,the development process and the present situation of dispensing technology was introduced as well as the related knowledge of piezoelectric stack; Then, the design scheme of jetting dispenser with flexible beam driven by two piezoelectric stacks was put forward according to the principle of mechanical collision jetting technology and the structure design of dispenser was completed based on it, meanwhile the micro-displacement amplification mechanism and the related structures of fluid was designed and analyzed in detail; In order to study the dynamic characteristics of the needle of the jetting dispenser, mathematical model of the dispenser analyzed by Matlab/Simulink was established to obtain the needle’s displacement curve and velocity curve. The influence of the main parameters on dynamic performance of the needle of the jetting dispenser was also analyzed, such as the driving voltage, the hinge stiffness, the mass of the needle, etc; Finally, the jetting dispensing experiment system was built based on the jetting dispenser prototype. The dynamic characteristics, jetting dispensing pattern, effect on the size of droplet, dispensing process, dots consistency of the jetting dispenser were studied in the experimental system. The experimental results show that the jetting dispensing valve designed with flexible beam driven by two piezoelectric stacks can achieve the maximum frequency up to200Hz, minimum volume of droplet about90nL, within the dots consistency±10%in stability. The performance of the jetting dispensing valve achieves the expected objectives.